JPH0527261U - Carburetor fuel cut solenoid valve - Google Patents

Abstract

(57) [Summary] Purpose-To completely prevent vapor generated from a solenoid valve placed in a horizontal direction with respect to a constant fuel liquid level formed in the carburetor from entering the fuel passage of the carburetor. A fuel cut solenoid valve for a carburetor capable of maintaining stable fuel control characteristics for a long period of time. Structure-Between the fuel valve seat provided on the inlet side of the fuel passage opening in the float chamber and the end of the solenoid valve facing the float chamber, in the float chamber, between the fuel valve seat and the fuel valve seat A first gap is formed between the end of the solenoid valve and the end of the solenoid valve, and a second gap is formed between the end of the float chamber and the inner bottom of the float chamber substantially orthogonal to the liquid surface. A partition wall extending toward the partition wall is provided, and the movable iron core of the solenoid valve is movably supported via a support hole formed in the partition wall.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a carburetor for adjusting and controlling the amount and concentration of an air-fuel mixture supplied to an engine, and in particular, a fuel passage for supplying fuel in a float chamber to a fuel injection hole opening in an intake passage is generated in a coil, The present invention relates to a fuel cut solenoid valve for a carburetor that controls opening and closing by the disappearing magnetic force.

[0002]

[Prior Art]

 As a fuel cut solenoid valve for a conventional carburetor, there is JP-A 64-19051. According to this, the outlet of the main nozzle is opened to the intake passage, and the inlet of the main nozzle is opened to the bottom of the float chamber via the fuel supply passage. The fuel supply passage is formed by connecting a vertically oriented inlet hole with a horizontally oriented outlet hole via a horizontally oriented valve chamber. Then, the inlet hole is connected to the float chamber and the outlet hole is connected to the main nozzle. A technique is disclosed in which a movable iron core of a solenoid valve that opens and closes an outlet hole is arranged in the valve chamber, and the upper part of the valve chamber, which is located in front of the outlet, communicates with the float chamber through an upward or inclined ventilation passage. Thus, the bubbles in the fuel that flowed into the valve chamber from the float chamber could be collected in the upper part near the outlet of the valve chamber and discharged into the float chamber from the ventilation passage.

[0003]

[Problems to be solved by the device]

 According to such a fuel cut solenoid valve of the conventional carburetor, the movable iron core of the solenoid valve is arranged substantially horizontally with respect to the constant fuel liquid level and below the constant fuel liquid level. On the other hand, looking at the movable iron core in the solenoid valve, the movable iron core is movably arranged in the guide hole of the coil bobbin around which the coil is wound and the guide hole of the housing. A gap of, for example, about 0.7 mm is formed between the guide holes so that the movable iron core can smoothly move within the guide hole. When such a solenoid valve is mounted below the constant liquid level of the carburetor to control the fuel, the fuel in the float chamber will flow into the gap between the outer periphery of the movable iron core and the guide hole of the coil bobbin. Here, when a current is applied to the coil of the solenoid valve for a long time, the coil self-heats, and this heat is transferred to the guide hole of the coil bobbin and is in the gap between the movable iron core and the guide hole of the coil bobbin. The fuel is heated and vapor is generated. After entering the valve chamber, this vapor is discharged into the float chamber through a ventilation path that opens in the upper part in front of the outlet of the valve chamber.

However, since the vapor is discharged from the vicinity of the outlet of the valve chamber through the ventilation passage, when the carburetor vibrates during the operation of the engine, the vapor in the valve chamber is further finely dispersed. However, according to this, the mass of the vapor becomes extremely light, so there is a risk that the vapor may enter the outlet hole and flow into the main nozzle, which is not preferable in terms of operating performance of the engine.

Further, the movable iron core is cantilevered by the guide hole of the guide hole housing of the coil bobbin of the solenoid valve, and there is a gap between the outer periphery of the movable iron core and the guide hole of the coil bobbin. Since the movable core vibrates during the operation of, the guide part may be worn during long-term use, and the obstruction of the fuel supply passage by the movable core may deteriorate.

Further, in order to solve the above-mentioned problems, it is possible to make the gap between the outer periphery of the movable iron core and the guide hole of the coil bobbin small, but according to this, sliding when the movable iron core moves in the guide hole of the coil bobbin. The resistance increases, and it is necessary to increase the magnetic force generated in the coil, which is not preferable because the solenoid valve becomes large.

The present invention has been made in view of the above problems, and can completely prevent the vapor generated from the solenoid valve from entering the fuel passage and has a stable fuel control characteristic for a long period of time. An object of the present invention is to provide a fuel cut solenoid valve for a carburetor that can be retained.

[0008]

[Means for Solving the Problems]

 According to the present invention, the float chamber main body is arranged on one side of the carburetor main body with the intake passage penetrating inside, and a constant fuel liquid level is formed in the float chamber formed by the carburetor main body and the float chamber main body. The fuel in the float chamber is supplied to the fuel injection hole opening in the intake passage through the fuel passage, and the fuel valve seat provided at the opening end of the fuel passage into the float chamber is generated by the magnetic force that causes and disappears in the coil. A fuel cut solenoid valve of a carburetor that moves and is placed substantially horizontal to the fuel liquid level and whose opening and closing is controlled by a solenoid valve equipped with a movable iron core provided with a valve portion at the end of the fuel opening into the float chamber. A first gap is formed between the fuel valve seat provided on the inlet side of the passage and the end of the solenoid valve facing the float chamber, facing the fuel valve seat and forming a first gap between the fuel valve seat and the end of the solenoid valve. , Facing the end of the solenoid valve and A second gap is formed in the partition wall, and a partition wall extending from the inner bottom of the float chamber to the fuel liquid surface is formed at a substantially right angle. The partition wall extends through the support hole through which the movable iron core of the solenoid valve is drilled. It is movably supported.

[0009]

[Action]

 The vapor generated in the gap between the outer periphery of the movable iron core of the solenoid valve and the inner periphery of the coil bobbin is discharged into the second gap, and is discharged into the float chamber through the second upper opening and the side portion above the vapor. Even if the vapor in the second gap enters the first gap through the gap between the support hole of the partition wall and the outer circumference of the movable iron core, it is discharged into the float chamber from the first upper opening and the side portion above the vapor. ..

On the other hand, the movable iron core is supported near one end thereof by the guide hole of the coil bobbin or the inner hole of the housing, and the other end thereof is supported by the supporting hole of the partition wall so that both ends thereof are supported. Vibration of the iron core is suppressed.

[0011]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. Reference numeral 1 denotes a carburetor main body in which an intake passage 2 penetrates, and a throttle valve 3 for variably controlling the intake passage area is arranged in the intake passage 2. A first fuel boss 4 projects downward from the lower side of the carburetor body 1.

A float chamber body 5 is arranged so as to face the lower recessed portion 1 A of the vaporizer body 1, and a float chamber 6 is formed by the vaporizer body 1 and the float chamber body 5.

In the float chamber 6, a horizontal constant fuel liquid level is formed by a known chamber liquid level control mechanism including a float 7, a float valve, and a valve seat (both not shown).

A second fuel boss 7 protruding upward is formed at the bottom of the float chamber body 5, and the lower end surface 4 A of the first fuel boss 4 and the upper end surface 7 A of the second fuel boss 7 are sealed by a seal member R. Contact each other through.

The carburetor main body 1 and the float chamber main body 5 have the male screw 8A provided at the tip of the holder 8 inserted in the second through hole 7A penetrating the second fuel boss 7 in the vertical direction. The first fuel boss 4 can be integrally attached by being screwed into the female screw 4B provided at the lower end of the first through hole 4C. However, it is not limited to this mounting method. Furthermore, a fuel valve seat V that opens in a substantially horizontal direction is formed on the outer periphery of the second fuel boss 7 that faces below the constant fuel liquid level of the float chamber 6, and this fuel valve seat V is the second fuel boss 7. An opening is formed in an annular gap D formed by the second through hole 7A inside and the outer periphery of the holder 8.

The fuel passage M is formed as follows. That is, 9 is a fuel injection hole such as a main nozzle that is arranged in the first through hole 4C and has one end opened to the intake passage 2, and a main fuel jet 10 is arranged below it. In the holder 8 arranged below the main fuel jet 10, one end opens to the first through hole 4C below the main fuel jet 10 (opens to the upper end surface of the holder 8) and the other end has an annular gap. A communication passage 8B is opened in D (opened to the side of the holder 8). In this embodiment, the fuel passage M becomes the fuel valve seat V-the annular gap D-the communication passage 8B of the holder 8-the main fuel jet 10-the fuel injection hole 9 from the upstream side of the fuel flow. Flowing.

W is a solenoid valve arranged in the horizontal direction and has the following configuration. A coil bobbin 11 having guide holes 11A formed in the horizontal direction is arranged in the housing 10, and a coil 12 is wound around the outer circumference of the coil bobbin 11. A male screw is formed on the left side protrusion of the housing 10, and the male screw is screwed to the side of the float chamber body 5. Thus, the end portion 10A of the solenoid valve W (specifically, the left end portion of the housing 10) faces the fuel valve seat V and opens into the floating chamber 6.

A fixed iron core 13 is fixedly arranged to the right of the guide hole 11 A of the coil bobbin 11, and a movable iron core 15 is arranged corresponding to the fixed iron core 13 via a spring 14 and a tip of the movable iron core 15 is also arranged. A valve portion 15A that can control the opening and closing of the fuel valve seat V is formed at.

The movable iron core 15 is supported movably in the horizontal direction in the guide hole 11 A of the coil bobbin 11 and the guide hole 10 B provided in the housing 10, and the left part of the movable iron core 15 protruding from the housing 10 is inside the float chamber 6. And the valve portion 15A can open and close the fuel valve seat V.

In the interior of the floating chamber 6 between the fuel valve seat V and the end portion 10A of the electromagnetic valve W facing the fuel valve seat V, the inner bottom portion 6A of the floating chamber 6 is positioned relative to the fuel level. A partition wall 16 that extends substantially orthogonally and extends upward is formed. The left side surface 16A of the partition wall 16 faces the fuel valve seat V, and the right side surface 16B faces the end portion 10A of the solenoid valve W opening to the float chamber 6. Thus, the first gap S 1 is formed between the left side surface 16A of the partition wall 16 and the fuel valve seat V, and the upper portion of the first gap S1 is located inside the floating chamber 6 at the first upper opening P1. And its sides are also open. On the other hand, a second gap S2 is formed between the right side surface 16B of the partition wall 16 and the end portion 10A of the electromagnetic valve W, and the upper portion of the second gap S2 is the second upper opening P2 at the floating chamber 6 It opens inside and its sides also open. The partition wall 16, the first gap S1, the first upper opening P1, the second gap S2, the second upper opening P2, and the side openings are well shown in FIG.

Reference numeral 17 is a support hole that is formed by penetrating the partition wall 16 in the horizontal direction, and slidably supports the movable iron core 15. Therefore, the movable iron core 15 is supported near the right end by the guide holes 10B and 11A of the housing 10 and the coil bobbin 11, and near the left end by the support hole 17 of the partition wall 16.

Next, the operation will be described. The solenoid valve W is energized prior to the operation of the engine, and the valve portion 15A of the movable iron core 15 opens the fuel valve seat V to allow the fuel passage M to communicate with the float chamber 6 to allow the fuel flow, while stopping the engine. At this time, the solenoid valve W is de-energized, and the valve portion 15A of the movable iron core 15 closes the fuel valve seat V to prevent the fuel from flowing into the fuel passage M.

When the electromagnetic valve W is continuously energized during engine operation, the coil 11 self-heats and the outer circumference of the movable iron core 15 and the coil bobbin 11 and the guide holes 11 A and 10 B of the housing 10 are separated. The fuel that has entered the gap is warmed and vapor is generated from this fuel.

According to the present invention, the vapor generated in the gap moves toward the end 10A of the housing 10 in the gap and is discharged from the end 10A into the second gap S2 in the floating chamber 6. To be done. Then, the vapor discharged into the second gap S2 moves upward by its own buoyancy, and is discharged into the float chamber 6 through the second upper opening P2 or the side opening of the second gap S2. The second gap S2 is formed by the right side surface 16B of the partition wall 16 and mainly the end portion 10A of the solenoid valve 10, and the side of the second gap S2 is sufficiently opened in addition to the second upper opening P2. Therefore, the vapor can be completely discharged into the floating chamber 6. On the other hand, when the vibration condition becomes extremely severe during the operation of the engine, the vapor discharged into the second gap S 2 is miniaturized, and the vapor becomes a gap between the support hole 17 of the partition wall 16 and the outer periphery of the movable iron core 15. Although it may be considered to enter the first gap S1, it may be completely discharged into the floating chamber 6 from the first upper opening P1 and the side opening of the first gap S1 even if it enters. This is because it was possible to form openings for sufficient discharge in the upper opening and the side openings by using the partition wall 16 instead of forming holes or chambers.

Thus, the vapor generated in the solenoid valve W does not enter the fuel passage M through the fuel valve seat V, and the drivability of the engine is not impaired.

On the other hand, when the engine is in operation, the movable iron core 15 vibrates, but the movable iron core 15 is guided and supported in the vicinity of its right end portion by the guide hole 10B of the housing 10 or the guide hole 11A of the coil bobbin 11, and the left end thereof. Since the vicinity of the part is supported by the support hole 17 of the partition wall 16 and supported by both ends, the movable iron core 15 is surely supported. The outer periphery of the movable iron core 15 generated by the vibration of the movable iron core 15 or The wear of the support holes 17 is suppressed, and stable obstruction of the valve portion 15A with respect to the fuel valve seat V can be maintained for a long period of time.

[0027]

[Effect of the device]

 According to the present invention, a partition wall extending upward from the inner bottom portion of the float chamber is provided in the float chamber between the fuel valve seat and the end of the solenoid valve, and the partition wall allows the upper and side portions thereof to be extended. Since the first gap and the second gap that open in the float chamber are separately provided, the vapor that has entered the second gap from the end of the solenoid valve has a large opening area. Good discharge from the side into the float chamber.

On the other hand, even if the vapor enters the first gap from the second gap through the support hole (referred to as a gap formed by the support hole and the movable iron core) provided in the partition wall, Similarly, it is discharged from the upper part and the side part of the first gap into the float chamber. As described above, most of the vapor is discharged into the float chamber through the second gap formed facing the end of the solenoid valve, and even if the vapor enters the first gap, this vapor is kept between the first gap and the first gap. Since the gas could be completely discharged into the float chamber from the gap, the vapor was completely prevented from entering the fuel passage, and the operability of the engine could be maintained well.

Further, since the movable iron core is guided in the vicinity of one end by the guide hole of the housing or the coil bobbin and is guided in the vicinity of the other end by the guide hole of the partition wall (supported by both ends guide), vibration of the movable iron core is suppressed. Therefore, the wear of the abutting portion can be eliminated, and stable obstruction of the valve portion with respect to the fuel valve seat can be maintained for a long period of time.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing an embodiment of a fuel cut solenoid valve of a carburetor according to the present invention.

FIG. 2 is a top plan view of only the float chamber main body in the embodiment of FIG.

FIG. 3 is an enlarged view of essential parts of the solenoid valve, the partition wall, the fuel valve seat, and the portion of FIG.

[Explanation of symbols]

 6 Float Chamber 6A Inner Bottom of Float Chamber 10A End of Solenoid Valve 15 Moving Iron Core 16 Partition Wall 17 Support Hole V Fuel Valve Seat W Solenoid Valve S1 First Gap S2 Second Gap

Claims (1)

[Scope of utility model registration request] 1. A float chamber main body is disposed on one side of a carburetor main body having an intake passage penetrating through the inside thereof, and a constant fuel liquid level is formed in a float chamber formed by the carburetor main body and the float chamber main body.
The fuel in the float chamber is supplied to the fuel injection hole opening in the intake passage through the fuel passage, and the fuel valve seat provided at the opening end of the fuel passage into the float chamber is moved by the magnetic force that occurs and disappears in the coil. In the fuel cut solenoid valve of the carburetor, which is opened and closed by a solenoid valve having a movable iron core provided with a valve portion at its end, the fuel cut solenoid valve having a fuel opening to the float chamber 6 In the floating chamber 6 between the fuel valve seat V provided on the inlet side of the passage M and the end 10A of the solenoid valve W facing the floating chamber 6, the fuel valve seat V is opposed to the fuel valve seat V. Forming a first gap S1 between the solenoid valve W and
End 10A of the solenoid valve W while facing the end 10A of
And a second gap S2 is formed between the inner bottom portion 6A of the float chamber 6 and
A partition wall 16 extending upward at substantially right angles to the fuel liquid level is provided, and the movable iron core 15 of the solenoid valve W is separated from the partition wall 1.
A fuel cut solenoid valve for a carburetor, which is movably supported through a support hole 17 formed in 6.